The Effect of Duration of Individual Housing on Social Behavior of Adult Male Bonnet Macaques (Macaca radiata).

Project constraints often require social primates, such as macaques, to be housed individually. However, we believed the amount of time spent housed alone prior to renewed social exposure would effect an animal's behavior. We observed the behavior of adult male bonnet macaques (Macaca radiata) during time spent in an exercise pen with other adult males. We studied 2 groups (n = 3 males/group). Group one (group LT) was composed of males that had been housed alone for 24 months prior to the study, and the other group (group ST) consisted of male macaques that had been housed alone for 1 month prior to the study. One day each week for 8 weeks, members of each group were placed in an exercise pen containing items that would encourage foraging and object exploration. Seven 5-min focal observations were recorded for macaques during each session. The 2 most notable differences in social behavior were that macaques of group LT spent significantly (P = 0.003) more time alone than did macaques of group ST, whereas macaques of group ST spent significantly (P = 0.002) more time involved in social grooming than did macaques of group LT. Thus, prior duration of prior individual housing appeared to significantly affect social behavior.